A cellular infiltrate is characteristic of anterior uveitis. Although these cells presumably contribute directly to the inflammatory process, little is known about what attracts these cells into the uveal tract. Monocytes and polymorphonuclear leukocytes are known to migrate in response to discrete chemical stimuli known as chemotactic factors. Preliminary work indicates that chemotactic activity is present in aqueous humor from animals and patients with active uveitis. Chemotactic activity will be analyzed in seven different animal models of anterior uveitis. Specific aims will be to 1) characterize and contrast aqueous humor chemotactic factors from these seven models; 2) quantitate chemotactic activity and correlate this with aqueous humor cell count; 3) test partially purified chemotactic factors from aqueous humor for their activity in vivo; 4) assess the effect of time on chemotactic activity in examples of sustained inflammation; 5) identify the cellular or tissue origin of chemotactic activity; and 6) study the effect of medications on aqueous humor chemotactic activity. The results of these studies may clarify the pathogenesis of a group of diseases of largely uncertain etiology.